Tightening device



Jan. 28, 1936. H. STANLEY E? AL 2,02%?334 TIGHTENING DEVICE 4Filed June20, 1954 INVENTORS M175 www1/Afm A TTORNEYS Patented Jan. 28, 1936UNITED STATES PATENT OFFICE TIGHTENING DEVICE Application June 20,

4 Claims.

This invention relates to tightening devices and is particularlyapplicable to tightening devices used for creating and maintainingtension upon strings such as are used in musical instruments.

An object of the invention is to provide an improved tensioning device.

Another object is to provide an improved tensioning device which willreceive the ends of a string of a musical instrument.

Another object is to provide an improved tensioning device which willfirmly hold strings subjected to relatively high tension.

Another object is to provide an improved tensioning device which will besimple in construction.

Another object is to provide an improved tensioning device which will beeasy of operation.

Other objects will hereinafter appear.

The invention will be better understood from the description of severalpractical embodiments thereof illustrated in the accompanying drawing;in which;

Figure 1 is a fragmentary perspective view of the outer end of the neckand head of a musical instrument, such as a guitar;

Figure 2 is a sectional View taken on the line II--II of Figure 1;

Figure 3 is a view similar to Figure 2 of a modified form of tighteningdevice; and

Figure 4 is a view also similar to Figure 2 of a further modificationthereof.

'I'he present tendency in string musical instruments is away fromstrings of the type made of gut or other animal or vegetable fibre andtoward metal strings such as are used in the piano and which generallyare made of steel, with or Without Wrapping, depending upon the pitch ofthe tone desired.

The use of metal strings introduces two problems which were not presentwith gut or similar strings; one, the strings, due to their greaterweight, must be strained to a much higher tension for a given note; andtwo, the ends of the wires, being stiff but of small diameter, are sharpand produce painful cuts and scratches and the like when one grips thehead of an instrument, as is done in adjusting or changing the strings.

The higher tension requires that the strings be much more firmly heldthan was previously necessary, as very slight amounts of slippage causethem to become seriously out of tune.

In Figure 1 is shown a part of the end of the neck of a stringinstrument, for this illustration 1934, Serial No. 731,492

a guitar having been chosen, the neck itself appearing at I, and theextension thereof or head being shown at 2. At the juncture of the headand neck is a bridge 3 which is notched for the reception of the usualstrings 4.

The strings vare secured in tightening devices shown as arranged in twogroups, one accessible from each side of the head, each group beingunited by a common base plate 5. Passing through this base plate andthrough holes in the wooden head are pins S, and secured to the lowerend of each pin as by a screw I threaded in the squared end 8 of the pinis a worm Wheel 9.

Journalled in depending lugs I0, formed upon the base 5, are shafts II,each provided on its inner end with a worm I2 meshing with the Wormwheel 9, and on its outer end with a flattened handle or a turning keyI3. The worm is of suiiiciently low pitch as to be self locking ornonreversible and so prevents any accidental unwinding of the string.The upper end of the pin 6 which extends above the wood of the head 2 isslotted, as indicated at I 4, and each pin is provided With an axialbore I5.

The operation of the device is as follows: The operator inserts the endof the wire string into the bore I5, as most clearly shown in Figure 2,and allows the string to extend sidewise through the slot. He thenrotates the handle I3, so turning the pin 6 upon its axis, which windsthe string about the pin, the string becoming abruptly bent where itleaves the slot I4 and so securely anchored.

The greater the tension which he applies to the string, the tighter itbinds against the corner of the slot, and it will be obvious that noends of the strings protrude to stick the fingers.

In Figure 3 is shown a modification of the pin of Figures l and 2 inwhich the external surface of the pin is made concave or grooved asindicated at IIB. The slot II4, instead of having parallel sides, isV-shaped so that the string wedges itself downwardly tightly into theslot. The groove IIB terminates at a point just above that at which thewidth of the slot II4 is approximately as great as the diameter of thestring intended to be inserted in it.

It will be apparent, therefore, that the first turn of the string,falling upon the tapering walls of the groove, tends to move the stringdownwardly toward the smallest diameter of the pin, and thus causes thesuccessive turns of the string to come below the slot, so that it isunnecessary to position it in this manner by hand.

Also, the tension upon the string causes it to Wedge tightly Within theV-shaped slot more rmly securing it in place than would be the case of aslot with parallel sides.

If the slot H4 be appreciably deeper than the point Where its widthequals the diameter of the string, the tension of the succeeding turnsof the string Will tend to spring the furcations of the end of the pintogether, increasing the clamping action upon the string in proportionto the tension applied to it, and similarlyincreasing the eiectivenesswith Which it is clamped.

In Figure 4 is a device is illustrated which is intended to be appliedto the head of an instrument having slots in which the strings areinserted and in which the pins are positioned. The base 2 HB5 is, inthis case, secured to the sides of the head instead of its bottom andthe pin 206 extends from one side across slot 2H, having its inner endreceived Within a recess in the head 202 and supported by the wall ofthis recess. The worm, worm Wheel and ha'ndle are similar to thosepreviously described.

The pin is provided with an .axial bore 215 with which communicates ahole 2l4 drilled through the side of the pin and which may be positionedradially thereof Vor inclined as illustrated in the drawing.

For this type of winding apparatus the end of the wire in insertedthrough hole 2|4 into bore 2|5 and the pin rotated by the handle, asabove described. The string is then wound upon the pin and held by thesharp bend which its tension creates at the outer end of hole 2M.

While we have described several illustrated embodiments of ourYinvention in some particularity, obviously many others will readilyoccur to those skilled in this art, and We do not, therefore, limitourselves to the precise details shown and described but claim as ourinvention all embodiments, variations and modifications thereof comingWithin the scope of the appended claims.

We claim:

1. A tensioning device comprising a pin rotatable about its axis andhaving an axial bore for the reception of the end of a string, meansenclosing the end .of said bore and an opening through the Wall of thepin to said axial bore.

2. A tensioning device comprising a` hollow cylindrical pin having adiametrically extending slot at one end.

3. A tensioning device comprising a hollow cylindrical pin having adiametrically extending slot at one end, said slot tapering from the endof said pm. '4. A tensioning device comprising a rotatable pin having abifurcated end, there being a gener-

